( function () {
/**
 * UnrealBloomPass is inspired by the bloom pass of Unreal Engine. It creates a
 * mip map chain of bloom textures and blurs them with different radii. Because
 * of the weighted combination of mips, and because larger blurs are done on
 * higher mips, this effect provides good quality and performance.
 *
 * Reference:
 * - https://docs.unrealengine.com/latest/INT/Engine/Rendering/PostProcessEffects/Bloom/
 */

class UnrealBloomPass extends THREE.Pass {
  constructor(resolution, strength, radius, threshold) {
    super();
    this.strength = strength !== undefined ? strength : 1;
    this.radius = radius;
    this.threshold = threshold;
    this.resolution = resolution !== undefined ? new THREE.Vector2(resolution.x, resolution.y) : new THREE.Vector2(256, 256); // create color only once here, reuse it later inside the render function

    this.clearColor = new THREE.Color(0, 0, 0); // render targets

    const pars = {
      minFilter: THREE.LinearFilter,
      magFilter: THREE.LinearFilter,
      format: THREE.RGBAFormat
    };
    this.renderTargetsHorizontal = [];
    this.renderTargetsVertical = [];
    this.nMips = 5;
    let resx = Math.round(this.resolution.x / 2);
    let resy = Math.round(this.resolution.y / 2);
    this.renderTargetBright = new THREE.WebGLRenderTarget(resx, resy, pars);
    this.renderTargetBright.texture.name = 'UnrealBloomPass.bright';
    this.renderTargetBright.texture.generateMipmaps = false;

    for (let i = 0; i < this.nMips; i++) {
      const renderTargetHorizonal = new THREE.WebGLRenderTarget(resx, resy, pars);
      renderTargetHorizonal.texture.name = 'UnrealBloomPass.h' + i;
      renderTargetHorizonal.texture.generateMipmaps = false;
      this.renderTargetsHorizontal.push(renderTargetHorizonal);
      const renderTargetVertical = new THREE.WebGLRenderTarget(resx, resy, pars);
      renderTargetVertical.texture.name = 'UnrealBloomPass.v' + i;
      renderTargetVertical.texture.generateMipmaps = false;
      this.renderTargetsVertical.push(renderTargetVertical);
      resx = Math.round(resx / 2);
      resy = Math.round(resy / 2);
    } // luminosity high pass material


    if (THREE.LuminosityHighPassShader === undefined) console.error('THREE.UnrealBloomPass relies on THREE.LuminosityHighPassShader');
    const highPassShader = THREE.LuminosityHighPassShader;
    this.highPassUniforms = THREE.UniformsUtils.clone(highPassShader.uniforms);
    this.highPassUniforms['luminosityThreshold'].value = threshold;
    this.highPassUniforms['smoothWidth'].value = 0.01;
    this.materialHighPassFilter = new THREE.ShaderMaterial({
      uniforms: this.highPassUniforms,
      vertexShader: highPassShader.vertexShader,
      fragmentShader: highPassShader.fragmentShader,
      defines: {}
    }); // Gaussian Blur Materials

    this.separableBlurMaterials = [];
    const kernelSizeArray = [3, 5, 7, 9, 11];
    resx = Math.round(this.resolution.x / 2);
    resy = Math.round(this.resolution.y / 2);

    for (let i = 0; i < this.nMips; i++) {
      this.separableBlurMaterials.push(this.getSeperableBlurMaterial(kernelSizeArray[i]));
      this.separableBlurMaterials[i].uniforms['texSize'].value = new THREE.Vector2(resx, resy);
      resx = Math.round(resx / 2);
      resy = Math.round(resy / 2);
    } // Composite material


    this.compositeMaterial = this.getCompositeMaterial(this.nMips);
    this.compositeMaterial.uniforms['blurTexture1'].value = this.renderTargetsVertical[0].texture;
    this.compositeMaterial.uniforms['blurTexture2'].value = this.renderTargetsVertical[1].texture;
    this.compositeMaterial.uniforms['blurTexture3'].value = this.renderTargetsVertical[2].texture;
    this.compositeMaterial.uniforms['blurTexture4'].value = this.renderTargetsVertical[3].texture;
    this.compositeMaterial.uniforms['blurTexture5'].value = this.renderTargetsVertical[4].texture;
    this.compositeMaterial.uniforms['bloomStrength'].value = strength;
    this.compositeMaterial.uniforms['bloomRadius'].value = 0.1;
    this.compositeMaterial.needsUpdate = true;
    const bloomFactors = [1.0, 0.8, 0.6, 0.4, 0.2];
    this.compositeMaterial.uniforms['bloomFactors'].value = bloomFactors;
    this.bloomTintColors = [new THREE.Vector3(1, 1, 1), new THREE.Vector3(1, 1, 1), new THREE.Vector3(1, 1, 1), new THREE.Vector3(1, 1, 1), new THREE.Vector3(1, 1, 1)];
    this.compositeMaterial.uniforms['bloomTintColors'].value = this.bloomTintColors; // copy material

    if (THREE.CopyShader === undefined) {
      console.error('THREE.UnrealBloomPass relies on THREE.CopyShader');
    }

    const copyShader = THREE.CopyShader;
    this.copyUniforms = THREE.UniformsUtils.clone(copyShader.uniforms);
    this.copyUniforms['opacity'].value = 1.0;
    this.materialCopy = new THREE.ShaderMaterial({
      uniforms: this.copyUniforms,
      vertexShader: copyShader.vertexShader,
      fragmentShader: copyShader.fragmentShader,
      blending: THREE.AdditiveBlending,
      depthTest: false,
      depthWrite: false,
      transparent: true
    });
    this.enabled = true;
    this.needsSwap = false;
    this._oldClearColor = new THREE.Color();
    this.oldClearAlpha = 1;
    this.basic = new THREE.MeshBasicMaterial();
    this.fsQuad = new THREE.FullScreenQuad(null);
  }

  dispose() {
    for (let i = 0; i < this.renderTargetsHorizontal.length; i++) {
      this.renderTargetsHorizontal[i].dispose();
    }

    for (let i = 0; i < this.renderTargetsVertical.length; i++) {
      this.renderTargetsVertical[i].dispose();
    }

    this.renderTargetBright.dispose();
  }

  setSize(width, height) {
    let resx = Math.round(width / 2);
    let resy = Math.round(height / 2);
    this.renderTargetBright.setSize(resx, resy);

    for (let i = 0; i < this.nMips; i++) {
      this.renderTargetsHorizontal[i].setSize(resx, resy);
      this.renderTargetsVertical[i].setSize(resx, resy);
      this.separableBlurMaterials[i].uniforms['texSize'].value = new THREE.Vector2(resx, resy);
      resx = Math.round(resx / 2);
      resy = Math.round(resy / 2);
    }
  }

  render(renderer, writeBuffer, readBuffer, deltaTime, maskActive) {
    renderer.getClearColor(this._oldClearColor);
    this.oldClearAlpha = renderer.getClearAlpha();
    const oldAutoClear = renderer.autoClear;
    renderer.autoClear = false;
    renderer.setClearColor(this.clearColor, 0);
    if (maskActive) renderer.state.buffers.stencil.setTest(false); // Render input to screen

    if (this.renderToScreen) {
      this.fsQuad.material = this.basic;
      this.basic.map = readBuffer.texture;
      renderer.setRenderTarget(null);
      renderer.clear();
      this.fsQuad.render(renderer);
    } // 1. Extract Bright Areas


    this.highPassUniforms['tDiffuse'].value = readBuffer.texture;
    this.highPassUniforms['luminosityThreshold'].value = this.threshold;
    this.fsQuad.material = this.materialHighPassFilter;
    renderer.setRenderTarget(this.renderTargetBright);
    renderer.clear();
    this.fsQuad.render(renderer); // 2. Blur All the mips progressively

    let inputRenderTarget = this.renderTargetBright;

    for (let i = 0; i < this.nMips; i++) {
      this.fsQuad.material = this.separableBlurMaterials[i];
      this.separableBlurMaterials[i].uniforms['colorTexture'].value = inputRenderTarget.texture;
      this.separableBlurMaterials[i].uniforms['direction'].value = UnrealBloomPass.BlurDirectionX;
      renderer.setRenderTarget(this.renderTargetsHorizontal[i]);
      renderer.clear();
      this.fsQuad.render(renderer);
      this.separableBlurMaterials[i].uniforms['colorTexture'].value = this.renderTargetsHorizontal[i].texture;
      this.separableBlurMaterials[i].uniforms['direction'].value = UnrealBloomPass.BlurDirectionY;
      renderer.setRenderTarget(this.renderTargetsVertical[i]);
      renderer.clear();
      this.fsQuad.render(renderer);
      inputRenderTarget = this.renderTargetsVertical[i];
    } // Composite All the mips


    this.fsQuad.material = this.compositeMaterial;
    this.compositeMaterial.uniforms['bloomStrength'].value = this.strength;
    this.compositeMaterial.uniforms['bloomRadius'].value = this.radius;
    this.compositeMaterial.uniforms['bloomTintColors'].value = this.bloomTintColors;
    renderer.setRenderTarget(this.renderTargetsHorizontal[0]);
    renderer.clear();
    this.fsQuad.render(renderer); // Blend it additively over the input texture

    this.fsQuad.material = this.materialCopy;
    this.copyUniforms['tDiffuse'].value = this.renderTargetsHorizontal[0].texture;
    if (maskActive) renderer.state.buffers.stencil.setTest(true);

    if (this.renderToScreen) {
      renderer.setRenderTarget(null);
      this.fsQuad.render(renderer);
    } else {
      renderer.setRenderTarget(readBuffer);
      this.fsQuad.render(renderer);
    } // Restore renderer settings


    renderer.setClearColor(this._oldClearColor, this.oldClearAlpha);
    renderer.autoClear = oldAutoClear;
  }

  getSeperableBlurMaterial(kernelRadius) {
    return new THREE.ShaderMaterial({
      defines: {
        'KERNEL_RADIUS': kernelRadius,
        'SIGMA': kernelRadius
      },
      uniforms: {
        'colorTexture': {
          value: null
        },
        'texSize': {
          value: new THREE.Vector2(0.5, 0.5)
        },
        'direction': {
          value: new THREE.Vector2(0.5, 0.5)
        }
      },
      vertexShader: `varying vec2 vUv;
				void main() {
					vUv = uv;
					gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );
				}`,
      fragmentShader: `#include <common>
				varying vec2 vUv;
				uniform sampler2D colorTexture;
				uniform vec2 texSize;
				uniform vec2 direction;

				float gaussianPdf(in float x, in float sigma) {
					return 0.39894 * exp( -0.5 * x * x/( sigma * sigma))/sigma;
				}
				void main() {
					vec2 invSize = 1.0 / texSize;
					float fSigma = float(SIGMA);
					float weightSum = gaussianPdf(0.0, fSigma);
					vec3 diffuseSum = texture2D( colorTexture, vUv).rgb * weightSum;
					for( int i = 1; i < KERNEL_RADIUS; i ++ ) {
						float x = float(i);
						float w = gaussianPdf(x, fSigma);
						vec2 uvOffset = direction * invSize * x;
						vec3 sample1 = texture2D( colorTexture, vUv + uvOffset).rgb;
						vec3 sample2 = texture2D( colorTexture, vUv - uvOffset).rgb;
						diffuseSum += (sample1 + sample2) * w;
						weightSum += 2.0 * w;
					}
					gl_FragColor = vec4(diffuseSum/weightSum, 1.0);
				}`
    });
  }

  getCompositeMaterial(nMips) {
    return new THREE.ShaderMaterial({
      defines: {
        'NUM_MIPS': nMips
      },
      uniforms: {
        'blurTexture1': {
          value: null
        },
        'blurTexture2': {
          value: null
        },
        'blurTexture3': {
          value: null
        },
        'blurTexture4': {
          value: null
        },
        'blurTexture5': {
          value: null
        },
        'dirtTexture': {
          value: null
        },
        'bloomStrength': {
          value: 1.0
        },
        'bloomFactors': {
          value: null
        },
        'bloomTintColors': {
          value: null
        },
        'bloomRadius': {
          value: 0.0
        }
      },
      vertexShader: `varying vec2 vUv;
				void main() {
					vUv = uv;
					gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );
				}`,
      fragmentShader: `varying vec2 vUv;
				uniform sampler2D blurTexture1;
				uniform sampler2D blurTexture2;
				uniform sampler2D blurTexture3;
				uniform sampler2D blurTexture4;
				uniform sampler2D blurTexture5;
				uniform sampler2D dirtTexture;
				uniform float bloomStrength;
				uniform float bloomRadius;
				uniform float bloomFactors[NUM_MIPS];
				uniform vec3 bloomTintColors[NUM_MIPS];

				float lerpBloomFactor(const in float factor) {
					float mirrorFactor = 1.2 - factor;
					return mix(factor, mirrorFactor, bloomRadius);
				}

				void main() {
					gl_FragColor = bloomStrength * ( lerpBloomFactor(bloomFactors[0]) * vec4(bloomTintColors[0], 1.0) * texture2D(blurTexture1, vUv) +
						lerpBloomFactor(bloomFactors[1]) * vec4(bloomTintColors[1], 1.0) * texture2D(blurTexture2, vUv) +
						lerpBloomFactor(bloomFactors[2]) * vec4(bloomTintColors[2], 1.0) * texture2D(blurTexture3, vUv) +
						lerpBloomFactor(bloomFactors[3]) * vec4(bloomTintColors[3], 1.0) * texture2D(blurTexture4, vUv) +
						lerpBloomFactor(bloomFactors[4]) * vec4(bloomTintColors[4], 1.0) * texture2D(blurTexture5, vUv) );
				}`
    });
  }

}

UnrealBloomPass.BlurDirectionX = new THREE.Vector2(1.0, 0.0);
UnrealBloomPass.BlurDirectionY = new THREE.Vector2(0.0, 1.0);

THREE.UnrealBloomPass = UnrealBloomPass;
} )();
